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Home My WebLink About3375; Maerkle Upper Chlorination Building Pump; Maerkle Upper Chlorination Building Pump; 1992-11-25KLE1NFELDE November 25, 1992 Project No. 51-1791-00-002 Mr. Richard E. Cook Principal Construction Inspector City of Carlsbad Engineering Department 2075 Las Palmas Drive Carlsbad, California 92009-1519 Subject: As-Graded Report Maerkle Upper Chlorination Building Pump Station and Disinfection Facilities, Carlsbad, California CMWD Project #89-109 Reference Report 1: Preliminary Geotechnical Investigation Proposed Upper Chlorination Building, Squires Reservoir, Costa Raul Municipal Water District Dated: July 31, 1989 Prepared by: Ninyo & Moore Reference Plans: Construction of Maerkle Pump Station and Disinfection Facilities Dated: February 14, 1992 Prepared by: Dudek & Associates, Inc. Reference Specifications: Contract Documents and Special Provisions for Construction of Maerkle Pump Station and Disinfection Facilities Dated: April 10, 1992 Prepared by: Dudek & Associates, Inc. Dear Mr. Cook: As requested, we have provided geotechnical testing and observation services during earthwork operations for the subject project. This report summarizes our test results and observations. The scope of our services consisted of: H Review of existing geotechnical report (Reference Report 1); • Observation and testing of earthwork operations for the upper Chlorination building pad; and, MLRl-92.1 Copyright 1992, Kleinfelder Page 1 of 4 KLEINFELDER 9555 Chesapeake Drive, Suite 101, San Diego, CA 92123 (619) 541-1145 Dynamic cone penetration testing of footings for evaluating allowable bearing capacity. SUMMARY Our testing and observation services were performed from October 28, 1992 through October 30, 1992 by a representative of our firm who was onsite on a periodic basis during grading operations. The contractor for the work was The Industrial Company San Diego, Inc. Approximately 12 to 18 inches of fill soil were placed in the upper chlorination building pad excavation prior to our scheduled arrival. The grading contractor pot-holed through the fill in the four corners of the building pad to permit our representative to spot check the subgrade below the fill. The bottom of the building pad was probed in the pot-holed locations by our representative with a 5/8-inch diameter, pointed steel rod and found to be generally firm and unyielding. Based on our review of these excavations, it is our opinion that the contractor prepared the subgrade in general conformance with the project plans and specifications. The building pad was undercut to a depth of approximately three feet below finish subgrade; the undercut extended laterally approximately five feet from the perimeter of the structure. Engineered fill consisting of onsite native soils were moisture conditioned, spread in the excavation in eight inch loose lifts, and compacted by mechanical means to the specification density. In-place density tests were performed in random locations in the bottom of the excavation and in the backfill soils in substantial conformance with ASTM test procedures D 2922 and D 3017 (nuclear method for density and moisture, respectively). The results of these tests at the specific locations tested are presented on Table 1 entitled "Compaction Test Summary." The maximum dry density and optimum moisture content of samples of fill soils were evaluated in our laboratory in substantial conformance with ASTM test procedure D1557. All tests met or exceeded the minimum compaction requirements of the specifications, and the results of these tests are presented on Table 2 entitled "Maximum Density Test Results." The expansion potential of a sample of fill soil was evaluated in our laboratory in substantial conformance with the Uniform Building Code Standards test procedure 29-2. The representative sample of soil tested for expansion exhibited a very low expansion potential. The results of this test is presented on Table 3 entitled "Expansion Test Results." At the completion of the earthwork operations, the contractor excavated the chlorination building footings. After probing the bottom of the footings to see that the surfaces were firm and unyielding, we completed cone soundings at two random locations in the bottom of the footings with a portable dynamic cone penetrometer. The cone soundings were MLRl-92.1 Page 2 of 4 Copyright 1992, Kleinfelder KLEINFELDER 9555 Chesapeake Drive, Suite 101, San Diego, CA 92123 (619) 541-1145 completed by driving a nominal 1.5-inch diameter cone into the soil with a free-falling, 35 pound hammer. Cone exploration depths ranged from 3.5 to 3.75 feet below the bottom of the footings. Our field representative logged the cone soundings in four inch (10 centimeter) increments. The actual blow counts in four inch (10 centimeter) increments were converted to dynamic cone resistance and equivalent SPT blow counts by computer program. A plot of dynamic cone resistance and evaluation of tested consistency were made for each sounding. The data for Cone Soundings 1 and 2 are attached as Plates 1 and 2, respectively. Based on our field observations and the borings from Reference Report 1, it is likely that the cone soundings were made in silty sand or weathered granitic bedrock (D.G.) with sand- like characteristics. The cone soundings made in the footing bottoms indicate that the allowable bearing capacity meets or exceeds the 2,500 psf provided in Reference Report 1. CONCLUSIONS The results of our tests and observations indicate that the earthwork operations our firm observed were performed in substantial conformance with the project specifications and referenced geotechnical report. The two cone soundings performed in the footing excavations indicate an allowable bearing capacity of 2,500 psf or more. CLOSURE The services provided as described in this report include professional opinions and judgements based on the data collected and our field observations. These services have been performed according to generally accepted geotechnical engineering practices that exist in the Carlsbad area at this time. No warranty, express or implied, is provided. The conclusions and recommendations contained herein apply to our work with respect to grading and represent conditions at the completions of the grading operations. Any subsequent grading should be done in conjunction with our observation and testing services. The term "observation" implies that we observed the progress of the work which was within our scope of services. Construction observation and testing should be performed during all footing and retaining wall excavations, placement of backfill for utility trenches, retaining walls, and granular fill placed prior to the placement of concrete for footings and for slab support. Our conclusions and opinions regarding general conformance with the referenced geotechnical report are based on our observations, experience, and testing. Subsurface conditions and the accuracy of tests used to measure such conditions can vary greatly at any time. MLRl-92.1 Page 3 of 4 Copyright 1992, Kleinfelder KLEINFELDER 9555 Chesapeake Drive, Suite 101, San Diego, CA 92123 (619) 541-1145 If any subsurface conditions are encountered subsequent to grading which are different from those described in our report, our firm should be notified immediately in case any supplemental recommendations may be necessary. We will not accept responsibility for any subsequent changes made to the site by others, by the uncontrolled action of water, or by the failure of others to properly repair damages caused by the uncontrolled action of water. This report may be used only by the client and only for the purposes stated within a reasonable time from its issuance. Land use, site conditions (both on-site and offsite), or other factors may change over time, and additional work may be required with the passage of time. Any party other than the client who wishes to use this report shall notify Kleinfelder of such intended use. Based on the intended use of the report, Kleinfelder may require that additional work be performed and that an updated report be issued. Non- compliance with any of these requirements by the client or anyone else will release Kleinfelder from any liability resulting from the use of this report by any unauthorized party. We sincerely appreciate the opportunity to be of service to you on this project. If you should have any questions concerning this report or require any additional services, please contact our office. Respectfully submitted, KLEINFELDER, INC. •$-*r~ JUL-C-, Ronald C. Thomson Operations Manager Rick E. Larson, G.E. 2027 Senior Engineer RCT/REL:mlm Attachments:Table 1 Compaction Test Summary Table 2 Maximum Density Test Results Table 3 Expansion Index Test Results Plate 1 Cone Sounding 1 Plate 2 Cone Sounding 2 MLRl-92.1 Copyright 1992, Kleinfelder Page 4 of 4 KLEINFELDER 9555 Chesapeake Drive, Suite 101, San Diego, CA 92123 (619) 541-1145 TABLES TABLE 1 COMPACTION TEST SUMMARY PROJECT NAME: Maerkle Pump Station PROJECTS 51-1791-00-002 DATE 10-28-92 10-28-92 10-28-92 10-28-92 10-29-92 10-29-92 10-30-92 10-30-92 TEST NO. 1 2 3 4 5 6 7 8 - RETEST OF NO.LOCATION S/E upper chlorination bldg. pond N/W upper chlorination bldg. pond Middle upper chlorination bldg. pond E. side upper chlorination bldg. pond W. side upper chlorination bldg. pond S. side upper chlorination bldg. pond N. side upper chlorination bldg. pond E. side upper chlorination bldg. pond ELEV. (FT) 505 504 507 507 509 509 FSG1> FSG MOIST (%) 125.0 124.2 126.6 123.7 124.5 124.9 125.6 126.9 DRY DENSITY 10.6 10.2 9.7 11.1 9.4 9.7 10.8 9.1 REL- COM?. (%) 96 95 97 95 96 96 96 93 • SOIL TYPE 3 3 3 3 3 3 3 3 RE- TESTED BY NO.REMARKS Pass Pass Pass Pass Pass Pass Pass Pass 1) FSG denotes finish subgrade Accepted engineering and testing procedures were used for these tests. The above data are presented for information purposes only. In the absence of continuous observation by our personnel at the site, we cannot express an opinion as to the adequacy of site preparation or overall site compaction. We do not undertake the guarantee of construction, nor do we relieve the contractor of his responsibility to produce a completed project conforming to the project plans and specifications. Copyright 1992 Kleinfelder, Inc.Sheet 1 TABLE 2 MAXIMUM DENSITY TEST RESULTS (LABORATORY AND FIELD) 51-1791-00-002 Sample Number 1 2 3 Description Brown silty Sand Light brown silty Sand (DG) Dark brown clayey Sand Optimum Moisture Content (Percent of Dry Weight) 9.0 7.8 9.0 Maximum Dry Density (Pcf) 126.5 124.8 130.2 KLEINFELDER 9555 Chesapeake Drive, Suite 101, San Diego, CA 92123 (619) 541-1145 LOCATION: SAMPLE: DATE PERFORMED: TABLES EXPANSION INDEX TEST RESULTS UBC 29-2 Upper Chlorination Building Pad 3 Dark brown clayey sand 11-2-92 51-1791-00-002 Expansion Index 4.9 Percent Swell 0.49% Expansion Potential Very low KLEINFELDER 9555 Chesapeake Drive, Suite 101, San Diego, CA 92123 (619) 541-1145 PLATES Kleinfelder, Inc. 9555 Chesapeake Dr., Suite 101 San Diego, California 92123 SHEET #: 1 OF 1 FILE #: 51-1791-01 WILDCAT DYNAMIC COMPLETED:!! -13-92 CONE LOG CREW: E.C. HOLE #: Cone 2, footing 3 north middle FOR: Maerkle Pump Station, Carlsbad, CA " LOCATION: Upper chlorination building pad DEPTH BLOWS RESISTANCE FT M PER 10 CM KG/OT2 0 I ' 1 0 A? ">7^ 1 ******i "I SURFACE ELEVATION: WATER ON COMPLETION: HAMMER WEIGHT: 35 LBS. CONE AREA: 10 SQ. CM CONE RESISTANCE TESTED CONSISTENCY 50 100 150 N' SAND SILT CLAY *** 12 MED. DENSE MED. DENSE STIFF NOTES: 1. This cone sounding was performed on the bottom of the excavated footing. 2. A dash (-) in the column for equivalent SPT N' value indicates the N' value is 25 or greater. 3. Based on Kleinfelder field observations and previous borings made at the site, it is likely that the subsurface material encountered by this sounding is sand or sand-like material; therefore, neglect tested consistency comments for silt and clay. •m KLEINFELDER PROJECT NO. 51-1791-00-002 PLATECONE SOUNDING 1 UPPER CHLORINATION BUILDING MAERKLE PUMP STATION 2 CARLSBAD, CALIFORNIA M -6 Kleinfelder, Inc. 9555 Chesapeake Dr., Suite 101 San Diego, California 92123 WILDCAT DYNAMIC CONE LOG SHEET #: 1 OF 1 FILE #: 51-1791-01 STARTED: 11-13-92 COMPLETED:11-13-92 CREW: E.C. HOLE #: Cone 1, footing a southwest corner FOR: Maerkle Pump Station, Carlsbad, CA LOCATION: Upper chlorination building pad SURFACE ELEVATION: UATER ON COMPLETION: HAMMER WEIGHT: 35 LBS. CONE AREA: 10 SQ. CM DEPTH BLOWS RESISTANCE FT M PER 10 CM KG/CM*2 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.1 19 14 22 23 23 36 36 32 27 47 48 84.4 62.2 97.7 102.1 102.1 159.8 159.8 142.1 119.9 208.7 185.3 ===================-============ CONE RESISTANCE 0 50 100 150 ************ s==========================================; TESTED CONSISTENCY N' SAND SILT CLAY 24 MED. DENSE 17 MED. DENSE - MED. DENSE - MED. DENSE - MED. DENSE - DENSE - DENSE - DENSE - DENSE - VERY DENSE - VERY DENSE MED. DENSE MED. DENSE MED. DENSE MED. DENSE MED. DENSE DENSE DENSE DENSE DENSE VERY DENSE VERY DENSE VERY STIFF VERY STIFF VERY STIFF VERY STIFF VERY STIFF HARD HARD HARD HARD HARD HARD NOTES: 1. This cone sounding was performed on the bottom of the excavated footing. 2. A dash (-) in the column for equivalent SPT N' value indicates the N' value is 25 or greater. 3. Based on Kleinfelder field observations and previous borings made at the site, it is likely that the subsurface material encountered by this sounding is sand or sand-like material; therefore, neglect tested consistency comments for silt and clay. KLEINFELDER PROJECT NO. 51-1791-00-002 M -6 CONE SOUNDING 1 UPPER CHLORINATION BUILDING MAERKLE PUMP STATION CARLSBAD, CALIFORNIA PLATE KLEINFELDER KLEINFELDER MEMORANDUM TO: Richard E. Cook/City of Carlsbad FROM: Rick E. Larson/Kleinfelder, Inc. DATE: November 17, 1992 "A7/? SUBJECT: Maerkle Pump Station and Disinfection Facilities Lower Pump Station Carlsbad, California KLEINFELDER PROJECT NO. 51-1791-00-002 Page 13 of the project geotechnical report recommends that footings be founded either entirely in fill or entirely in formational material. The report does not address subgrade treatment for the slab. If the slab is placed on cut-fill transition soils, the potential for cracking may be increased. To reduce the potential for cracking, we recommend that the slab be constructed on a uniform subgrade consisting of either entirely on formational material or a uniform fill thickness. The uniform fill thickness should be 12 inches or the depth of the thickest fill, beneath the floor slab, whichever is less. If you have any questions, or need additional information, please contact our office. cc: Bill Lopez Carlsbad Municipal Water District KLEINFELDER 9555 Chesapeake Drive, Suite 101, San Diego, CA 92123 (619) 541-1145